<!doctype html><html lang="en">
 <head>
  <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
  <meta content="width=device-width, initial-scale=1, shrink-to-fit=no" name="viewport">
  <title>Gyroscope</title>
  <meta content="ED" name="w3c-status">
<style data-fill-with="stylesheet">/******************************************************************************
 *                   Style sheet for the W3C specifications                   *
 *
 * Special classes handled by this style sheet include:
 *
 * Indices
 *   - .toc for the Table of Contents (<ol class="toc">)
 *     + <span class="secno"> for the section numbers
 *   - #toc for the Table of Contents (<nav id="toc">)
 *   - ul.index for Indices (<a href="#ref">term</a><span>, in §N.M</span>)
 *   - table.index for Index Tables (e.g. for properties or elements)
 *
 * Structural Markup
 *   - table.data for general data tables
 *     -> use 'scope' attribute, <colgroup>, <thead>, and <tbody> for best results !
 *     -> use <table class='complex data'> for extra-complex tables
 *     -> use <td class='long'> for paragraph-length cell content
 *     -> use <td class='pre'> when manual line breaks/indentation would help readability
 *   - dl.switch for switch statements
 *   - ol.algorithm for algorithms (helps to visualize nesting)
 *   - .figure and .caption (HTML4) and figure and figcaption (HTML5)
 *     -> .sidefigure for right-floated figures
 *   - ins/del
 *
 * Code
 *   - pre and code
 *
 * Special Sections
 *   - .note       for informative notes             (div, p, span, aside, details)
 *   - .example    for informative examples          (div, p, pre, span)
 *   - .issue      for issues                        (div, p, span)
 *   - .assertion  for assertions                    (div, p, span)
 *   - .advisement for loud normative statements     (div, p, strong)
 *   - .annoying-warning for spec obsoletion notices (div, aside, details)
 *
 * Definition Boxes
 *   - pre.def   for WebIDL definitions
 *   - table.def for tables that define other entities (e.g. CSS properties)
 *   - dl.def    for definition lists that define other entitles (e.g. HTML elements)
 *
 * Numbering
 *   - .secno for section numbers in .toc and headings (<span class='secno'>3.2</span>)
 *   - .marker for source-inserted example/figure/issue numbers (<span class='marker'>Issue 4</span>)
 *   - ::before styled for CSS-generated issue/example/figure numbers:
 *     -> Documents wishing to use this only need to add
 *        figcaption::before,
 *        .caption::before { content: "Figure "  counter(figure) " ";  }
 *        .example::before { content: "Example " counter(example) " "; }
 *        .issue::before   { content: "Issue "   counter(issue) " ";   }
 *
 * Header Stuff (ignore, just don't conflict with these classes)
 *   - .head for the header
 *   - .copyright for the copyright
 *
 * Miscellaneous
 *   - .overlarge for things that should be as wide as possible, even if
 *     that overflows the body text area. This can be used on an item or
 *     on its container, depending on the effect desired.
 *     Note that this styling basically doesn't help at all when printing,
 *     since A4 paper isn't much wider than the max-width here.
 *     It's better to design things to fit into a narrower measure if possible.
 *   - js-added ToC jump links (see fixup.js)
 *
 ******************************************************************************/

/******************************************************************************/
/*                                   Body                                     */
/******************************************************************************/

	body {
		counter-reset: example figure issue;

		/* Layout */
		max-width: 50em;               /* limit line length to 50em for readability   */
		margin: 0 auto;                /* center text within page                     */
		padding: 1.6em 1.5em 2em 50px; /* assume 16px font size for downlevel clients */
		padding: 1.6em 1.5em 2em calc(26px + 1.5em); /* leave space for status flag     */

		/* Typography */
		line-height: 1.5;
		font-family: sans-serif;
		widows: 2;
		orphans: 2;
		word-wrap: break-word;
		overflow-wrap: break-word;
		hyphens: auto;

		/* Colors */
		color: black;
		background: white top left fixed no-repeat;
		background-size: 25px auto;
	}


/******************************************************************************/
/*                         Front Matter & Navigation                          */
/******************************************************************************/

/** Header ********************************************************************/

	div.head { margin-bottom: 1em }
	div.head hr { border-style: solid; }

	div.head h1 {
		font-weight: bold;
		margin: 0 0 .1em;
		font-size: 220%;
	}

	div.head h2 { margin-bottom: 1.5em;}

/** W3C Logo ******************************************************************/

	.head .logo {
		float: right;
		margin: 0.4rem 0 0.2rem .4rem;
	}

	.head img[src*="logos/W3C"] {
		display: block;
		border: solid #1a5e9a;
		border-width: .65rem .7rem .6rem;
		border-radius: .4rem;
		background: #1a5e9a;
		color: white;
		font-weight: bold;
	}

	.head a:hover > img[src*="logos/W3C"],
	.head a:focus > img[src*="logos/W3C"] {
		opacity: .8;
	}

	.head a:active > img[src*="logos/W3C"] {
		background: #c00;
		border-color: #c00;
	}

	/* see also additional rules in Link Styling section */

/** Copyright *****************************************************************/

	p.copyright,
	p.copyright small { font-size: small }

/** Back to Top / ToC Toggle **************************************************/

	@media print {
		#toc-nav {
			display: none;
		}
	}
	@media not print {
		#toc-nav {
			position: fixed;
			z-index: 2;
			bottom: 0; left: 0;
			margin: 0;
			min-width: 1.33em;
			border-top-right-radius: 2rem;
			box-shadow: 0 0 2px;
			font-size: 1.5em;
			color: black;
		}
		#toc-nav > a {
			display: block;
			white-space: nowrap;

			height: 1.33em;
			padding: .1em 0.3em;
			margin: 0;

			background: white;
			box-shadow: 0 0 2px;
			border: none;
			border-top-right-radius: 1.33em;
			background: white;
		}
		#toc-nav > #toc-jump {
			padding-bottom: 2em;
			margin-bottom: -1.9em;
		}

		#toc-nav > a:hover,
		#toc-nav > a:focus {
			background: #f8f8f8;
		}
		#toc-nav > a:not(:hover):not(:focus) {
			color: #707070;
		}

		/* statusbar gets in the way on keyboard focus; remove once browsers fix */
		#toc-nav > a[href="#toc"]:not(:hover):focus:last-child {
			padding-bottom: 1.5rem;
		}

		#toc-nav:not(:hover) > a:not(:focus) > span + span {
			/* Ideally this uses :focus-within on #toc-nav */
			display: none;
		}
		#toc-nav > a > span + span {
			padding-right: 0.2em;
		}

		#toc-toggle-inline {
			vertical-align: 0.05em;
			font-size: 80%;
			color: gray;
			color: hsla(203,20%,40%,.7);
			border-style: none;
			background: transparent;
			position: relative;
		}
		#toc-toggle-inline:hover:not(:active),
		#toc-toggle-inline:focus:not(:active) {
			text-shadow: 1px 1px silver;
			top: -1px;
			left: -1px;
		}

		#toc-nav :active {
			color: #C00;
		}
	}

/** ToC Sidebar ***************************************************************/

	/* Floating sidebar */
	@media screen {
		body.toc-sidebar #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			max-width: 80%;
			max-width: calc(100% - 2em - 26px);
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			background: inherit;
			background-color: #f7f8f9;
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
		}
		body.toc-sidebar #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
		}
		body.toc-sidebar #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
		}
	}
	/* Hide main scroller when only the ToC is visible anyway */
	@media screen and (max-width: 28em) {
		body.toc-sidebar {
			overflow: hidden;
		}
	}

	/* Sidebar with its own space */
	@media screen and (min-width: 78em) {
		body:not(.toc-inline) #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			background: inherit;
			background-color: #f7f8f9;
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
		}
		body:not(.toc-inline) #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
		}

		body:not(.toc-inline) {
			padding-left: 29em;
		}
		/* See also Overflow section at the bottom */

		body:not(.toc-inline) #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
		}
	}
	@media screen and (min-width: 90em) {
		body:not(.toc-inline) {
			margin: 0 4em;
		}
	}

/******************************************************************************/
/*                                Sectioning                                  */
/******************************************************************************/

/** Headings ******************************************************************/

	h1, h2, h3, h4, h5, h6, dt {
		page-break-after: avoid;
		page-break-inside: avoid;
		font: 100% sans-serif;   /* Reset all font styling to clear out UA styles */
		font-family: inherit;    /* Inherit the font family. */
		line-height: 1.2;        /* Keep wrapped headings compact */
		hyphens: manual;         /* Hyphenated headings look weird */
	}

	h2, h3, h4, h5, h6 {
		margin-top: 3rem;
	}

	h1, h2, h3 {
		color: #005A9C;
		background: transparent;
	}

	h1 { font-size: 170%; }
	h2 { font-size: 140%; }
	h3 { font-size: 120%; }
	h4 { font-weight: bold; }
	h5 { font-style: italic; }
	h6 { font-variant: small-caps; }
	dt { font-weight: bold; }

/** Subheadings ***************************************************************/

	h1 + h2,
	#subtitle {
		/* #subtitle is a subtitle in an H2 under the H1 */
		margin-top: 0;
	}
	h2 + h3,
	h3 + h4,
	h4 + h5,
	h5 + h6 {
		margin-top: 1.2em; /* = 1 x line-height */
	}

/** Section divider ***********************************************************/

	:not(.head) > hr {
		font-size: 1.5em;
		text-align: center;
		margin: 1em auto;
		height: auto;
		border: transparent solid 0;
		background: transparent;
	}
	:not(.head) > hr::before {
		content: "\2727\2003\2003\2727\2003\2003\2727";
	}

/******************************************************************************/
/*                            Paragraphs and Lists                            */
/******************************************************************************/

	p {
		margin: 1em 0;
	}

	dd > p:first-child,
	li > p:first-child {
		margin-top: 0;
	}

	ul, ol {
		margin-left: 0;
		padding-left: 2em;
	}

	li {
		margin: 0.25em 0 0.5em;
		padding: 0;
	}

	dl dd {
		margin: 0 0 .5em 2em;
	}

	.head dd + dd { /* compact for header */
		margin-top: -.5em;
	}

	/* Style for algorithms */
	ol.algorithm ol:not(.algorithm),
	.algorithm > ol ol:not(.algorithm) {
	 border-left: 0.5em solid #DEF;
	}

	/* Put nice boxes around each algorithm. */
	[data-algorithm]:not(.heading) {
	  padding: .5em;
	  border: thin solid #ddd; border-radius: .5em;
	  margin: .5em calc(-0.5em - 1px);
	}
	[data-algorithm]:not(.heading) > :first-child {
	  margin-top: 0;
	}
	[data-algorithm]:not(.heading) > :last-child {
	  margin-bottom: 0;
	}

	/* Style for switch/case <dl>s */
	dl.switch > dd > ol.only,
	dl.switch > dd > .only > ol {
	 margin-left: 0;
	}
	dl.switch > dd > ol.algorithm,
	dl.switch > dd > .algorithm > ol {
	 margin-left: -2em;
	}
	dl.switch {
	 padding-left: 2em;
	}
	dl.switch > dt {
	 text-indent: -1.5em;
	 margin-top: 1em;
	}
	dl.switch > dt + dt {
	 margin-top: 0;
	}
	dl.switch > dt::before {
	 content: '\21AA';
	 padding: 0 0.5em 0 0;
	 display: inline-block;
	 width: 1em;
	 text-align: right;
	 line-height: 0.5em;
	}

/** Terminology Markup ********************************************************/


/******************************************************************************/
/*                                 Inline Markup                              */
/******************************************************************************/

/** Terminology Markup ********************************************************/
	dfn   { /* Defining instance */
		font-weight: bolder;
	}
	a > i { /* Instance of term */
		font-style: normal;
	}
	dt dfn code, code.idl {
		font-size: medium;
	}
	dfn var {
		font-style: normal;
	}

/** Change Marking ************************************************************/

	del { color: red;  text-decoration: line-through; }
	ins { color: #080; text-decoration: underline;    }

/** Miscellaneous improvements to inline formatting ***************************/

	sup {
		vertical-align: super;
		font-size: 80%
	}

/******************************************************************************/
/*                                    Code                                    */
/******************************************************************************/

/** General monospace/pre rules ***********************************************/

	pre, code, samp {
		font-family: Menlo, Consolas, "DejaVu Sans Mono", Monaco, monospace;
		font-size: .9em;
		page-break-inside: avoid;
		hyphens: none;
		text-transform: none;
	}
	pre code,
	code code {
		font-size: 100%;
	}

	pre {
		margin-top: 1em;
		margin-bottom: 1em;
		overflow: auto;
	}

/** Inline Code fragments *****************************************************/

  /* Do something nice. */

/******************************************************************************/
/*                                    Links                                   */
/******************************************************************************/

/** General Hyperlinks ********************************************************/

	/* We hyperlink a lot, so make it less intrusive */
	a[href] {
		color: #034575;
		text-decoration: none;
		border-bottom: 1px solid #707070;
		/* Need a bit of extending for it to look okay */
		padding: 0 1px 0;
		margin: 0 -1px 0;
	}
	a:visited {
		border-bottom-color: #BBB;
	}

	/* Use distinguishing colors when user is interacting with the link */
	a[href]:focus,
	a[href]:hover {
		background: #f8f8f8;
		background: rgba(75%, 75%, 75%, .25);
		border-bottom-width: 3px;
		margin-bottom: -2px;
	}
	a[href]:active {
		color: #C00;
		border-color: #C00;
	}

	/* Backout above styling for W3C logo */
	.head .logo,
	.head .logo a {
		border: none;
		text-decoration: none;
		background: transparent;
	}

/******************************************************************************/
/*                                    Images                                  */
/******************************************************************************/

	img {
		border-style: none;
	}

	/* For autogen numbers, add
	   .caption::before, figcaption::before { content: "Figure " counter(figure) ". "; }
	*/

	figure, .figure, .sidefigure {
		page-break-inside: avoid;
		text-align: center;
		margin: 2.5em 0;
	}
	.figure img,    .sidefigure img,    figure img,
	.figure object, .sidefigure object, figure object {
		max-width: 100%;
		margin: auto;
	}
	.figure pre, .sidefigure pre, figure pre {
		text-align: left;
		display: table;
		margin: 1em auto;
	}
	.figure table, figure table {
		margin: auto;
	}
	@media screen and (min-width: 20em) {
		.sidefigure {
			float: right;
			width: 50%;
			margin: 0 0 0.5em 0.5em
		}
	}
	.caption, figcaption, caption {
		font-style: italic;
		font-size: 90%;
	}
	.caption::before, figcaption::before, figcaption > .marker {
		font-weight: bold;
	}
	.caption, figcaption {
		counter-increment: figure;
	}

	/* DL list is indented 2em, but figure inside it is not */
	dd > .figure, dd > figure { margin-left: -2em }

/******************************************************************************/
/*                             Colored Boxes                                  */
/******************************************************************************/

	.issue, .note, .example, .assertion, .advisement, blockquote {
		padding: .5em;
		border: .5em;
		border-left-style: solid;
		page-break-inside: avoid;
	}
	span.issue, span.note {
		padding: .1em .5em .15em;
		border-right-style: solid;
	}

	.issue,
	.note,
	.example,
	.advisement,
	.assertion,
	blockquote {
		margin: 1em auto;
	}
	.note  > p:first-child,
	.issue > p:first-child,
	blockquote > :first-child {
		margin-top: 0;
	}
	blockquote > :last-child {
		margin-bottom: 0;
	}

/** Blockquotes ***************************************************************/

	blockquote {
		border-color: silver;
	}

/** Open issue ****************************************************************/

	.issue {
		border-color: #E05252;
		background: #FBE9E9;
		counter-increment: issue;
		overflow: auto;
	}
	.issue::before, .issue > .marker {
		text-transform: uppercase;
		color: #AE1E1E;
		padding-right: 1em;
		text-transform: uppercase;
	}
	/* Add .issue::before { content: "Issue " counter(issue) " "; } for autogen numbers,
	   or use class="marker" to mark up the issue number in source. */

/** Example *******************************************************************/

	.example {
		border-color: #E0CB52;
		background: #FCFAEE;
		counter-increment: example;
		overflow: auto;
		clear: both;
	}
	.example::before, .example > .marker {
		text-transform: uppercase;
		color: #827017;
		min-width: 7.5em;
		display: block;
	}
	/* Add .example::before { content: "Example " counter(example) " "; } for autogen numbers,
	   or use class="marker" to mark up the example number in source. */

/** Non-normative Note ********************************************************/

	.note {
		border-color: #52E052;
		background: #E9FBE9;
		overflow: auto;
	}

	.note::before, .note > .marker,
	details.note > summary::before,
	details.note > summary > .marker {
		text-transform: uppercase;
		display: block;
		color: hsl(120, 70%, 30%);
	}
	/* Add .note::before { content: "Note"; } for autogen label,
	   or use class="marker" to mark up the label in source. */

	details.note > summary {
		display: block;
		color: hsl(120, 70%, 30%);
	}
	details.note[open] > summary {
		border-bottom: 1px silver solid;
	}

/** Assertion Box *************************************************************/
	/*  for assertions in algorithms */

	.assertion {
		border-color: #AAA;
		background: #EEE;
	}

/** Advisement Box ************************************************************/
	/*  for attention-grabbing normative statements */

	.advisement {
		border-color: orange;
		border-style: none solid;
		background: #FFEECC;
	}
	strong.advisement {
		display: block;
		text-align: center;
	}
	.advisement > .marker {
		color: #B35F00;
	}

/** Spec Obsoletion Notice ****************************************************/
	/* obnoxious obsoletion notice for older/abandoned specs. */

	details {
		display: block;
	}
	summary {
		font-weight: bolder;
	}

	.annoying-warning:not(details),
	details.annoying-warning:not([open]) > summary,
	details.annoying-warning[open] {
		background: #fdd;
		color: red;
		font-weight: bold;
		padding: .75em 1em;
		border: thick red;
		border-style: solid;
		border-radius: 1em;
	}
	.annoying-warning :last-child {
		margin-bottom: 0;
	}

@media not print {
	details.annoying-warning[open] {
		position: fixed;
		left: 1em;
		right: 1em;
		bottom: 1em;
		z-index: 1000;
	}
}

	details.annoying-warning:not([open]) > summary {
		text-align: center;
	}

/** Entity Definition Boxes ***************************************************/

	.def {
		padding: .5em 1em;
		background: #DEF;
		margin: 1.2em 0;
		border-left: 0.5em solid #8CCBF2;
	}

/******************************************************************************/
/*                                    Tables                                  */
/******************************************************************************/

	th, td {
		text-align: left;
		text-align: start;
	}

/** Property/Descriptor Definition Tables *************************************/

	table.def {
		/* inherits .def box styling, see above */
		width: 100%;
		border-spacing: 0;
	}

	table.def td,
	table.def th {
		padding: 0.5em;
		vertical-align: baseline;
		border-bottom: 1px solid #bbd7e9;
	}

	table.def > tbody > tr:last-child th,
	table.def > tbody > tr:last-child td {
		border-bottom: 0;
	}

	table.def th {
		font-style: italic;
		font-weight: normal;
		padding-left: 1em;
		width: 3em;
	}

	/* For when values are extra-complex and need formatting for readability */
	table td.pre {
		white-space: pre-wrap;
	}

	/* A footnote at the bottom of a def table */
	table.def           td.footnote {
		padding-top: 0.6em;
	}
	table.def           td.footnote::before {
		content: " ";
		display: block;
		height: 0.6em;
		width: 4em;
		border-top: thin solid;
	}

/** Data tables (and properly marked-up index tables) *************************/
	/*
		 <table class="data"> highlights structural relationships in a table
		 when correct markup is used (e.g. thead/tbody, th vs. td, scope attribute)

		 Use class="complex data" for particularly complicated tables --
		 (This will draw more lines: busier, but clearer.)

		 Use class="long" on table cells with paragraph-like contents
		 (This will adjust text alignment accordingly.)
		 Alternately use class="longlastcol" on tables, to have the last column assume "long".
	*/

	table {
		word-wrap: normal;
		overflow-wrap: normal;
		hyphens: manual;
	}

	table.data,
	table.index {
		margin: 1em auto;
		border-collapse: collapse;
		border: hidden;
		width: 100%;
	}
	table.data caption,
	table.index caption {
		max-width: 50em;
		margin: 0 auto 1em;
	}

	table.data td,  table.data th,
	table.index td, table.index th {
		padding: 0.5em 1em;
		border-width: 1px;
		border-color: silver;
		border-top-style: solid;
	}

	table.data thead td:empty {
		padding: 0;
		border: 0;
	}

	table.data  thead,
	table.index thead,
	table.data  tbody,
	table.index tbody {
		border-bottom: 2px solid;
	}

	table.data colgroup,
	table.index colgroup {
		border-left: 2px solid;
	}

	table.data  tbody th:first-child,
	table.index tbody th:first-child  {
		border-right: 2px solid;
		border-top: 1px solid silver;
		padding-right: 1em;
	}

	table.data th[colspan],
	table.data td[colspan] {
		text-align: center;
	}

	table.complex.data th,
	table.complex.data td {
		border: 1px solid silver;
		text-align: center;
	}

	table.data.longlastcol td:last-child,
	table.data td.long {
	 vertical-align: baseline;
	 text-align: left;
	}

	table.data img {
		vertical-align: middle;
	}


/*
Alternate table alignment rules

	table.data,
	table.index {
		text-align: center;
	}

	table.data  thead th[scope="row"],
	table.index thead th[scope="row"] {
		text-align: right;
	}

	table.data  tbody th:first-child,
	table.index tbody th:first-child  {
		text-align: right;
	}

Possible extra rowspan handling

	table.data  tbody th[rowspan]:not([rowspan='1']),
	table.index tbody th[rowspan]:not([rowspan='1']),
	table.data  tbody td[rowspan]:not([rowspan='1']),
	table.index tbody td[rowspan]:not([rowspan='1']) {
		border-left: 1px solid silver;
	}

	table.data  tbody th[rowspan]:first-child,
	table.index tbody th[rowspan]:first-child,
	table.data  tbody td[rowspan]:first-child,
	table.index tbody td[rowspan]:first-child{
		border-left: 0;
		border-right: 1px solid silver;
	}
*/

/******************************************************************************/
/*                                  Indices                                   */
/******************************************************************************/


/** Table of Contents *********************************************************/

	.toc a {
		/* More spacing; use padding to make it part of the click target. */
		padding-top: 0.1rem;
		/* Larger, more consistently-sized click target */
		display: block;
		/* Reverse color scheme */
		color: black;
		border-color: #3980B5;
		border-bottom-width: 3px !important;
		margin-bottom: 0px !important;
	}
	.toc a:visited {
		border-color: #054572;
	}
	.toc a:not(:focus):not(:hover) {
		/* Allow colors to cascade through from link styling */
		border-bottom-color: transparent;
	}

	.toc, .toc ol, .toc ul, .toc li {
		list-style: none; /* Numbers must be inlined into source */
		/* because generated content isn't search/selectable and markers can't do multilevel yet */
		margin:  0;
		padding: 0;
		line-height: 1.1rem; /* consistent spacing */
	}

	/* ToC not indented until third level, but font style & margins show hierarchy */
	.toc > li             { font-weight: bold;   }
	.toc > li li          { font-weight: normal; }
	.toc > li li li       { font-size:   95%;    }
	.toc > li li li li    { font-size:   90%;    }
	.toc > li li li li .secno { font-size: 85%; }
	.toc > li li li li li { font-size:   85%;    }
	.toc > li li li li li .secno { font-size: 100%; }

	/* @supports not (display:grid) { */
		.toc > li             { margin: 1.5rem 0;    }
		.toc > li li          { margin: 0.3rem 0;    }
		.toc > li li li       { margin-left: 2rem;   }

		/* Section numbers in a column of their own */
		.toc .secno {
			float: left;
			width: 4rem;
			white-space: nowrap;
		}

		.toc li {
			clear: both;
		}

		:not(li) > .toc              { margin-left:  5rem; }
		.toc .secno                  { margin-left: -5rem; }
		.toc > li li li .secno       { margin-left: -7rem; }
		.toc > li li li li .secno    { margin-left: -9rem; }
		.toc > li li li li li .secno { margin-left: -11rem; }

		/* Tighten up indentation in narrow ToCs */
		@media (max-width: 30em) {
			:not(li) > .toc              { margin-left:  4rem; }
			.toc .secno                  { margin-left: -4rem; }
			.toc > li li li              { margin-left:  1rem; }
			.toc > li li li .secno       { margin-left: -5rem; }
			.toc > li li li li .secno    { margin-left: -6rem; }
			.toc > li li li li li .secno { margin-left: -7rem; }
		}
	/* } */

	@supports (display:grid) and (display:contents) {
		/* Use #toc over .toc to override non-@supports rules. */
		#toc {
			display: grid;
			align-content: start;
			grid-template-columns: auto 1fr;
			grid-column-gap: 1rem;
			column-gap: 1rem;
			grid-row-gap: .6rem;
			row-gap: .6rem;
		}
		#toc h2 {
			grid-column: 1 / -1;
			margin-bottom: 0;
		}
		#toc ol,
		#toc li,
		#toc a {
			display: contents;
			/* Switch <a> to subgrid when supported */
		}
		#toc span {
			margin: 0;
		}
		#toc > .toc > li > a > span {
			/* The spans of the top-level list,
			   comprising the first items of each top-level section. */
			margin-top: 1.1rem;
		}
		#toc#toc .secno { /* Ugh, need more specificity to override base.css */
			grid-column: 1;
			width: auto;
			margin-left: 0;
		}
		#toc .content {
			grid-column: 2;
			width: auto;
			margin-right: 1rem;
		}
		#toc .content:hover {
			background: rgba(75%, 75%, 75%, .25);
			border-bottom: 3px solid #054572;
			margin-bottom: -3px;
		}
		#toc li li li .content {
			margin-left: 1rem;
		}
		#toc li li li li .content {
			margin-left: 2rem;
		}
	}


/** Index *********************************************************************/

	/* Index Lists: Layout */
	ul.index       { margin-left: 0; columns: 15em; text-indent: 1em hanging; }
	ul.index li    { margin-left: 0; list-style: none; break-inside: avoid; }
	ul.index li li { margin-left: 1em }
	ul.index dl    { margin-top: 0; }
	ul.index dt    { margin: .2em 0 .2em 20px;}
	ul.index dd    { margin: .2em 0 .2em 40px;}
	/* Index Lists: Typography */
	ul.index ul,
	ul.index dl { font-size: smaller; }
	@media not print {
		ul.index li span {
			white-space: nowrap;
			color: transparent; }
		ul.index li a:hover + span,
		ul.index li a:focus + span {
			color: #707070;
		}
	}

/** Index Tables *****************************************************/
	/* See also the data table styling section, which this effectively subclasses */

	table.index {
		font-size: small;
		border-collapse: collapse;
		border-spacing: 0;
		text-align: left;
		margin: 1em 0;
	}

	table.index td,
	table.index th {
		padding: 0.4em;
	}

	table.index tr:hover td:not([rowspan]),
	table.index tr:hover th:not([rowspan]) {
		background: #f7f8f9;
	}

	/* The link in the first column in the property table (formerly a TD) */
	table.index th:first-child a {
		font-weight: bold;
	}

/******************************************************************************/
/*                                    Print                                   */
/******************************************************************************/

	@media print {
		/* Pages have their own margins. */
		html {
			margin: 0;
		}
		/* Serif for print. */
		body {
			font-family: serif;
		}
	}
	@page {
		margin: 1.5cm 1.1cm;
	}

/******************************************************************************/
/*                                    Legacy                                  */
/******************************************************************************/

	/* This rule is inherited from past style sheets. No idea what it's for. */
	.hide { display: none }



/******************************************************************************/
/*                             Overflow Control                               */
/******************************************************************************/

	.figure .caption, .sidefigure .caption, figcaption {
		/* in case figure is overlarge, limit caption to 50em */
		max-width: 50rem;
		margin-left: auto;
		margin-right: auto;
	}
	.overlarge {
		/* Magic to create good table positioning:
		   "content column" is 50ems wide at max; less on smaller screens.
		   Extra space (after ToC + content) is empty on the right.

		   1. When table < content column, centers table in column.
		   2. When content < table < available, left-aligns.
		   3. When table > available, fills available + scroll bar.
		*/ 
		display: grid;
		grid-template-columns: minmax(0, 50em);
	}
	.overlarge > table {
		/* limit preferred width of table */
		max-width: 50em;
		margin-left: auto;
		margin-right: auto;
	}

	@media (min-width: 55em) {
		.overlarge {
			margin-right: calc(13px + 26.5rem - 50vw);
			max-width: none;
		}
	}
	@media screen and (min-width: 78em) {
		body:not(.toc-inline) .overlarge {
			/* 30.5em body padding 50em content area */
			margin-right: calc(40em - 50vw) !important;
		}
	}
	@media screen and (min-width: 90em) {
		body:not(.toc-inline) .overlarge {
			/* 4em html margin 30.5em body padding 50em content area */
			margin-right: calc(84.5em - 100vw) !important;
		}
	}

	@media not print {
		.overlarge {
			overflow-x: auto;
			/* See Lea Verou's explanation background-attachment:
			 * http://lea.verou.me/2012/04/background-attachment-local/
			 *
			background: top left  / 4em 100% linear-gradient(to right,  #ffffff, rgba(255, 255, 255, 0)) local,
			            top right / 4em 100% linear-gradient(to left, #ffffff, rgba(255, 255, 255, 0)) local,
			            top left  / 1em 100% linear-gradient(to right,  #c3c3c5, rgba(195, 195, 197, 0)) scroll,
			            top right / 1em 100% linear-gradient(to left, #c3c3c5, rgba(195, 195, 197, 0)) scroll,
			            white;
			background-repeat: no-repeat;
			*/
		}
	}
</style>
<style>
    body {
      background: url("https://www.w3.org/StyleSheets/TR/logo-ED") top left no-repeat white;
      background-attachment: fixed;
    }
  </style>
  <link href="https://www.w3.org/TR/gyroscope/" rel="canonical">
<style>/* style-md-lists */

/* This is a weird hack for me not yet following the commonmark spec
   regarding paragraph and lists. */
[data-md] > :first-child {
    margin-top: 0;
}
[data-md] > :last-child {
    margin-bottom: 0;
}</style>
<style>/* style-selflinks */

.heading, .issue, .note, .example, li, dt {
    position: relative;
}
a.self-link {
    position: absolute;
    top: 0;
    left: calc(-1 * (3.5rem - 26px));
    width: calc(3.5rem - 26px);
    height: 2em;
    text-align: center;
    border: none;
    transition: opacity .2s;
    opacity: .5;
}
a.self-link:hover {
    opacity: 1;
}
.heading > a.self-link {
    font-size: 83%;
}
li > a.self-link {
    left: calc(-1 * (3.5rem - 26px) - 2em);
}
dfn > a.self-link {
    top: auto;
    left: auto;
    opacity: 0;
    width: 1.5em;
    height: 1.5em;
    background: gray;
    color: white;
    font-style: normal;
    transition: opacity .2s, background-color .2s, color .2s;
}
dfn:hover > a.self-link {
    opacity: 1;
}
dfn > a.self-link:hover {
    color: black;
}

a.self-link::before            { content: "¶"; }
.heading > a.self-link::before { content: "§"; }
dfn > a.self-link::before      { content: "#"; }</style>
<style>/* style-counters */

body {
    counter-reset: example figure issue;
}
.issue {
    counter-increment: issue;
}
.issue:not(.no-marker)::before {
    content: "Issue " counter(issue);
}

.example {
    counter-increment: example;
}
.example:not(.no-marker)::before {
    content: "Example " counter(example);
}
.invalid.example:not(.no-marker)::before,
.illegal.example:not(.no-marker)::before {
    content: "Invalid Example" counter(example);
}

figcaption {
    counter-increment: figure;
}
figcaption:not(.no-marker)::before {
    content: "Figure " counter(figure) " ";
}</style>
<style>/* style-var-click-highlighting */

    var { cursor: pointer; }
    var.selected0 { background-color: #F4D200; box-shadow: 0 0 0 2px #F4D200; }
    var.selected1 { background-color: #FF87A2; box-shadow: 0 0 0 2px #FF87A2; }
    var.selected2 { background-color: #96E885; box-shadow: 0 0 0 2px #96E885; }
    var.selected3 { background-color: #3EEED2; box-shadow: 0 0 0 2px #3EEED2; }
    var.selected4 { background-color: #EACFB6; box-shadow: 0 0 0 2px #EACFB6; }
    var.selected5 { background-color: #82DDFF; box-shadow: 0 0 0 2px #82DDFF; }
    var.selected6 { background-color: #FFBCF2; box-shadow: 0 0 0 2px #FFBCF2; }
    </style>
<style>/* style-autolinks */

.css.css, .property.property, .descriptor.descriptor {
    color: #005a9c;
    font-size: inherit;
    font-family: inherit;
}
.css::before, .property::before, .descriptor::before {
    content: "‘";
}
.css::after, .property::after, .descriptor::after {
    content: "’";
}
.property, .descriptor {
    /* Don't wrap property and descriptor names */
    white-space: nowrap;
}
.type { /* CSS value <type> */
    font-style: italic;
}
pre .property::before, pre .property::after {
    content: "";
}
[data-link-type="property"]::before,
[data-link-type="propdesc"]::before,
[data-link-type="descriptor"]::before,
[data-link-type="value"]::before,
[data-link-type="function"]::before,
[data-link-type="at-rule"]::before,
[data-link-type="selector"]::before,
[data-link-type="maybe"]::before {
    content: "‘";
}
[data-link-type="property"]::after,
[data-link-type="propdesc"]::after,
[data-link-type="descriptor"]::after,
[data-link-type="value"]::after,
[data-link-type="function"]::after,
[data-link-type="at-rule"]::after,
[data-link-type="selector"]::after,
[data-link-type="maybe"]::after {
    content: "’";
}

[data-link-type].production::before,
[data-link-type].production::after,
.prod [data-link-type]::before,
.prod [data-link-type]::after {
    content: "";
}

[data-link-type=element],
[data-link-type=element-attr] {
    font-family: Menlo, Consolas, "DejaVu Sans Mono", monospace;
    font-size: .9em;
}
[data-link-type=element]::before { content: "<" }
[data-link-type=element]::after  { content: ">" }

[data-link-type=biblio] {
    white-space: pre;
}</style>
<style>/* style-dfn-panel */

.dfn-panel {
    position: absolute;
    z-index: 35;
    height: auto;
    width: -webkit-fit-content;
    width: fit-content;
    max-width: 300px;
    max-height: 500px;
    overflow: auto;
    padding: 0.5em 0.75em;
    font: small Helvetica Neue, sans-serif, Droid Sans Fallback;
    background: #DDDDDD;
    color: black;
    border: outset 0.2em;
}
.dfn-panel:not(.on) { display: none; }
.dfn-panel * { margin: 0; padding: 0; text-indent: 0; }
.dfn-panel > b { display: block; }
.dfn-panel a { color: black; }
.dfn-panel a:not(:hover) { text-decoration: none !important; border-bottom: none !important; }
.dfn-panel > b + b { margin-top: 0.25em; }
.dfn-panel ul { padding: 0; }
.dfn-panel li { list-style: inside; }
.dfn-panel.activated {
    display: inline-block;
    position: fixed;
    left: .5em;
    bottom: 2em;
    margin: 0 auto;
    max-width: calc(100vw - 1.5em - .4em - .5em);
    max-height: 30vh;
}

.dfn-paneled { cursor: pointer; }
</style>
<style>/* style-syntax-highlighting */
pre.idl.highlight { color: #708090; }
.highlight:not(.idl) { background: hsl(24, 20%, 95%); }
code.highlight { padding: .1em; border-radius: .3em; }
pre.highlight, pre > code.highlight { display: block; padding: 1em; margin: .5em 0; overflow: auto; border-radius: 0; }
c-[a] { color: #990055 } /* Keyword.Declaration */
c-[b] { color: #990055 } /* Keyword.Type */
c-[c] { color: #708090 } /* Comment */
c-[d] { color: #708090 } /* Comment.Multiline */
c-[e] { color: #0077aa } /* Name.Attribute */
c-[f] { color: #669900 } /* Name.Tag */
c-[g] { color: #222222 } /* Name.Variable */
c-[k] { color: #990055 } /* Keyword */
c-[l] { color: #000000 } /* Literal */
c-[m] { color: #000000 } /* Literal.Number */
c-[n] { color: #0077aa } /* Name */
c-[o] { color: #999999 } /* Operator */
c-[p] { color: #999999 } /* Punctuation */
c-[s] { color: #a67f59 } /* Literal.String */
c-[t] { color: #a67f59 } /* Literal.String.Single */
c-[u] { color: #a67f59 } /* Literal.String.Double */
c-[cp] { color: #708090 } /* Comment.Preproc */
c-[c1] { color: #708090 } /* Comment.Single */
c-[cs] { color: #708090 } /* Comment.Special */
c-[kc] { color: #990055 } /* Keyword.Constant */
c-[kn] { color: #990055 } /* Keyword.Namespace */
c-[kp] { color: #990055 } /* Keyword.Pseudo */
c-[kr] { color: #990055 } /* Keyword.Reserved */
c-[ld] { color: #000000 } /* Literal.Date */
c-[nc] { color: #0077aa } /* Name.Class */
c-[no] { color: #0077aa } /* Name.Constant */
c-[nd] { color: #0077aa } /* Name.Decorator */
c-[ni] { color: #0077aa } /* Name.Entity */
c-[ne] { color: #0077aa } /* Name.Exception */
c-[nf] { color: #0077aa } /* Name.Function */
c-[nl] { color: #0077aa } /* Name.Label */
c-[nn] { color: #0077aa } /* Name.Namespace */
c-[py] { color: #0077aa } /* Name.Property */
c-[ow] { color: #999999 } /* Operator.Word */
c-[mb] { color: #000000 } /* Literal.Number.Bin */
c-[mf] { color: #000000 } /* Literal.Number.Float */
c-[mh] { color: #000000 } /* Literal.Number.Hex */
c-[mi] { color: #000000 } /* Literal.Number.Integer */
c-[mo] { color: #000000 } /* Literal.Number.Oct */
c-[sb] { color: #a67f59 } /* Literal.String.Backtick */
c-[sc] { color: #a67f59 } /* Literal.String.Char */
c-[sd] { color: #a67f59 } /* Literal.String.Doc */
c-[se] { color: #a67f59 } /* Literal.String.Escape */
c-[sh] { color: #a67f59 } /* Literal.String.Heredoc */
c-[si] { color: #a67f59 } /* Literal.String.Interpol */
c-[sx] { color: #a67f59 } /* Literal.String.Other */
c-[sr] { color: #a67f59 } /* Literal.String.Regex */
c-[ss] { color: #a67f59 } /* Literal.String.Symbol */
c-[vc] { color: #0077aa } /* Name.Variable.Class */
c-[vg] { color: #0077aa } /* Name.Variable.Global */
c-[vi] { color: #0077aa } /* Name.Variable.Instance */
c-[il] { color: #000000 } /* Literal.Number.Integer.Long */
</style>
 <body class="h-entry">
  <div class="head">
   <p data-fill-with="logo"><a class="logo" href="https://www.w3.org/"> <img alt="W3C" height="48" src="https://www.w3.org/StyleSheets/TR/2016/logos/W3C" width="72"> </a> </p>
   <h1 class="p-name no-ref" id="title">Gyroscope</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Editor’s Draft, <time class="dt-updated" datetime="1970-01-01">1 January 1970</time></span></h2>
   <div data-fill-with="spec-metadata">
    <dl>
     <dt>This version:
     <dd><a class="u-url" href="https://w3c.github.io/gyroscope/">https://w3c.github.io/gyroscope/</a>
     <dt>Latest published version:
     <dd><a href="https://www.w3.org/TR/gyroscope/">https://www.w3.org/TR/gyroscope/</a>
     <dt>Previous Versions:
     <dd><a href="https://www.w3.org/TR/2019/WD-gyroscope-20190307/" rel="prev">https://www.w3.org/TR/2019/WD-gyroscope-20190307/</a>
     <dt>Version History:
     <dd><a href="https://github.com/w3c/gyroscope/commits/master/index.bs">https://github.com/w3c/gyroscope/commits/master/index.bs</a>
     <dt>Feedback:
     <dd><span><a href="mailto:public-device-apis@w3.org?subject=%5Bgyroscope%5D%20YOUR%20TOPIC%20HERE">public-device-apis@w3.org</a> with subject line “<kbd>[gyroscope] <i data-lt>… message topic …</i></kbd>” (<a href="https://lists.w3.org/Archives/Public/public-device-apis/" rel="discussion">archives</a>)</span>
     <dt class="editor">Editor:
     <dd class="editor p-author h-card vcard" data-editor-id="41974"><a class="p-name fn u-url url" href="http://intel.com/">Anssi Kostiainen</a> (<span class="p-org org">Intel Corporation</span>)
     <dt class="editor">Former Editor:
     <dd class="editor p-author h-card vcard" data-editor-id="78325"><a class="p-name fn u-url url" href="http://intel.com/">Mikhail Pozdnyakov</a> (<span class="p-org org">Intel Corporation</span>)
     <dt>Bug Reports:
     <dd><a href="https://www.github.com/w3c/gyroscope/issues/new">via the w3c/gyroscope repository on GitHub</a>
     <dt>Test Suite:
     <dd><a href="https://github.com/web-platform-tests/wpt/tree/master/gyroscope">web-platform-tests on GitHub</a>
    </dl>
   </div>
   <div data-fill-with="warning"></div>
   <p class="copyright" data-fill-with="copyright"><a href="https://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 1970 <a href="https://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a href="https://www.csail.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>, <a href="https://www.ercim.eu/"><abbr title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="https://www.keio.ac.jp/">Keio</a>, <a href="https://ev.buaa.edu.cn/">Beihang</a>). W3C <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="https://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document" rel="license">permissive document license</a> rules apply. </p>
   <hr title="Separator for header">
  </div>
  <div class="p-summary" data-fill-with="abstract">
   <h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
   <p>This specification defines a concrete sensor interface to monitor

  the rate of rotation around the device’s local three primary axes.</p>
  </div>
  <h2 class="no-num no-toc no-ref heading settled" id="sotd"><span class="content">Status of this document</span></h2>
  <div data-fill-with="status">
   <p> This is a public copy of the editors’ draft.
	It is provided for discussion only and may change at any moment.
	Its publication here does not imply endorsement of its contents by W3C.
	Don’t cite this document other than as work in progress. </p>
   <p> If you wish to make comments regarding this document, please send them to <a href="mailto:public-device-apis@w3.org?Subject=%5Bgyroscope%5D%20PUT%20SUBJECT%20HERE">public-device-apis@w3.org</a> (<a href="mailto:public-device-apis-request@w3.org?subject=subscribe">subscribe</a>, <a href="https://lists.w3.org/Archives/Public/public-device-apis/">archives</a>).
	When sending e-mail,
	please put the text “gyroscope” in the subject,
	preferably like this:
	“[gyroscope] <em>…summary of comment…</em>”.
	All comments are welcome. </p>
   <p> This document was produced by the <a href="https://www.w3.org/das/">Devices and Sensors Working Group</a>. </p>
   <p> This document was produced by a group operating under
	the <a href="https://www.w3.org/Consortium/Patent-Policy/">W3C Patent Policy</a>.
	W3C maintains a <a href="https://www.w3.org/2004/01/pp-impl/43696/status" rel="disclosure">public list of any patent disclosures</a> made in connection with the deliverables of the group;
	that page also includes instructions for disclosing a patent.
	An individual who has actual knowledge of a patent which the individual believes contains <a href="https://www.w3.org/Consortium/Patent-Policy/#def-essential">Essential Claim(s)</a> must disclose the information in accordance with <a href="https://www.w3.org/Consortium/Patent-Policy/#sec-Disclosure">section 6 of the W3C Patent Policy</a>. </p>
   <p> This document is governed by the <a href="https://www.w3.org/2019/Process-20190301/" id="w3c_process_revision">1 March 2019 W3C Process Document</a>. </p>
   <p></p>
  </div>
  <div data-fill-with="at-risk"></div>
  <nav data-fill-with="table-of-contents" id="toc">
   <h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
   <ol class="toc" role="directory">
    <li><a href="#intro"><span class="secno">1</span> <span class="content">Introduction</span></a>
    <li><a href="#usecases-requirements"><span class="secno">2</span> <span class="content">Use Cases and Requirements</span></a>
    <li><a href="#examples"><span class="secno">3</span> <span class="content">Examples</span></a>
    <li><a href="#security-and-privacy"><span class="secno">4</span> <span class="content">Security and Privacy Considerations</span></a>
    <li>
     <a href="#model"><span class="secno">5</span> <span class="content">Model</span></a>
     <ol class="toc">
      <li><a href="#reference-frame"><span class="secno">5.1</span> <span class="content">Reference Frame</span></a>
     </ol>
    <li>
     <a href="#api"><span class="secno">6</span> <span class="content">API</span></a>
     <ol class="toc">
      <li>
       <a href="#gyroscope-interface"><span class="secno">6.1</span> <span class="content">The Gyroscope Interface</span></a>
       <ol class="toc">
        <li><a href="#gyroscope-x"><span class="secno">6.1.1</span> <span class="content">Gyroscope.x</span></a>
        <li><a href="#gyroscope-y"><span class="secno">6.1.2</span> <span class="content">Gyroscope.y</span></a>
        <li><a href="#gyroscope-z"><span class="secno">6.1.3</span> <span class="content">Gyroscope.z</span></a>
       </ol>
     </ol>
    <li>
     <a href="#abstract-operations"><span class="secno">7</span> <span class="content">Abstract Operations</span></a>
     <ol class="toc">
      <li><a href="#construct-a-gyroscope-object"><span class="secno">7.1</span> <span class="content">Construct a Gyroscope object</span></a>
     </ol>
    <li>
     <a href="#automation"><span class="secno">8</span> <span class="content">Automation</span></a>
     <ol class="toc">
      <li><a href="#mock-gyroscope-type"><span class="secno">8.1</span> <span class="content">Mock Sensor Type</span></a>
     </ol>
    <li><a href="#acknowledgements"><span class="secno">9</span> <span class="content">Acknowledgements</span></a>
    <li><a href="#conformance"><span class="secno">10</span> <span class="content">Conformance</span></a>
    <li>
     <a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
     <ol class="toc">
      <li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
      <li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
     </ol>
    <li>
     <a href="#references"><span class="secno"></span> <span class="content">References</span></a>
     <ol class="toc">
      <li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
      <li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
     </ol>
    <li><a href="#idl-index"><span class="secno"></span> <span class="content">IDL Index</span></a>
   </ol>
  </nav>
  <main>
   <h2 class="heading settled" data-level="1" id="intro"><span class="secno">1. </span><span class="content">Introduction</span><a class="self-link" href="#intro"></a></h2>
   <p>The Gyroscope API extends the Generic Sensor API <a data-link-type="biblio" href="#biblio-generic-sensor">[GENERIC-SENSOR]</a> to provide information about the angular velocity around the device’s local X, Y and Z axis
in terms of radian per seconds units.</p>
   <h2 class="heading settled" data-level="2" id="usecases-requirements"><span class="secno">2. </span><span class="content">Use Cases and Requirements</span><a class="self-link" href="#usecases-requirements"></a></h2>
   <p>The use cases and requirements are addressed in the <cite><a href="https://w3c.github.io/motion-sensors/#usecases-and-requirements"> Motion Sensors Explainer</a></cite> document.</p>
   <h2 class="heading settled" data-level="3" id="examples"><span class="secno">3. </span><span class="content">Examples</span><a class="self-link" href="#examples"></a></h2>
   <div class="example" id="example-8845580c">
    <a class="self-link" href="#example-8845580c"></a> 
<pre class="highlight"><c- a>let</c-> sensor <c- o>=</c-> <c- k>new</c-> Gyroscope<c- p>();</c->
sensor<c- p>.</c->start<c- p>();</c->

sensor<c- p>.</c->onreading <c- o>=</c-> <c- p>()</c-> <c- p>=></c-> <c- p>{</c->
    console<c- p>.</c->log<c- p>(</c-><c- u>"Angular velocity around the X-axis "</c-> <c- o>+</c-> sensor<c- p>.</c->x<c- p>);</c->
    console<c- p>.</c->log<c- p>(</c-><c- u>"Angular velocity around the Y-axis "</c-> <c- o>+</c-> sensor<c- p>.</c->y<c- p>);</c->
    console<c- p>.</c->log<c- p>(</c-><c- u>"Angular velocity around the Z-axis "</c-> <c- o>+</c-> sensor<c- p>.</c->z<c- p>);</c->
<c- p>};</c->

sensor<c- p>.</c->onerror <c- o>=</c-> event <c- p>=></c-> console<c- p>.</c->log<c- p>(</c->event<c- p>.</c->error<c- p>.</c->name<c- p>,</c-> event<c- p>.</c->error<c- p>.</c->message<c- p>);</c->
</pre>
   </div>
   <h2 class="heading settled" data-level="4" id="security-and-privacy"><span class="secno">4. </span><span class="content">Security and Privacy Considerations</span><a class="self-link" href="#security-and-privacy"></a></h2>
   <p><a data-link-type="dfn" href="https://w3c.github.io/sensors/#sensor-reading" id="ref-for-sensor-reading">Sensor readings</a> provided by inertial sensors, such as gyroscope, could be used by adversaries
to exploit various security threats, for example, <a data-link-type="dfn" href="https://w3c.github.io/sensors/#keystroke-monitoring" id="ref-for-keystroke-monitoring">keylogging</a>, <a data-link-type="dfn" href="https://w3c.github.io/sensors/#location-tracking" id="ref-for-location-tracking">location tracking</a>, <a data-link-type="dfn" href="https://w3c.github.io/sensors/#device-fingerprinting" id="ref-for-device-fingerprinting">fingerprinting</a>, <a data-link-type="dfn" href="https://w3c.github.io/sensors/#user-identifying" id="ref-for-user-identifying">user identifying</a> and even <a data-link-type="dfn" href="https://w3c.github.io/sensors/#eavesdropping" id="ref-for-eavesdropping">eavesdropping</a>.</p>
   <p>Research papers published by security community, for instance, <a data-link-type="biblio" href="#biblio-keystrokedefense">[KEYSTROKEDEFENSE]</a>, indicate that
by throttling the frequency, risks of successful attacks are not fully eliminated, while throttling
may greatly affect usefulness of a web application with legitimate reasons to use the sensors.</p>
   <p>The <a data-link-type="biblio" href="#biblio-touchsignatures">[TOUCHSIGNATURES]</a> research paper proposes that implementations can provide visual indication when
inertial sensors are in use and/or require explicit user consent to access <a data-link-type="dfn" href="https://w3c.github.io/sensors/#sensor-reading" id="ref-for-sensor-reading①">sensor readings</a>.
These mitigation strategies complement the <a data-link-type="dfn" href="https://w3c.github.io/sensors/#mitigation-strategies" id="ref-for-mitigation-strategies">generic mitigations</a> defined
in the Generic Sensor API <a data-link-type="biblio" href="#biblio-generic-sensor">[GENERIC-SENSOR]</a>.</p>
   <h2 class="heading settled" data-level="5" id="model"><span class="secno">5. </span><span class="content">Model</span><a class="self-link" href="#model"></a></h2>
   <p>The <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="gyroscope-sensor-type">Gyroscope</dfn> <a data-link-type="dfn" href="https://w3c.github.io/sensors/#sensor-type" id="ref-for-sensor-type">sensor type</a>’s associated <code class="idl"><a data-link-type="idl" href="https://w3c.github.io/sensors/#sensor" id="ref-for-sensor">Sensor</a></code> subclass is the <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope">Gyroscope</a></code> class.</p>
   <p>The <a data-link-type="dfn" href="#gyroscope-sensor-type" id="ref-for-gyroscope-sensor-type">Gyroscope</a> has a <a data-link-type="dfn" href="https://w3c.github.io/sensors/#default-sensor" id="ref-for-default-sensor">default sensor</a>, which is the device’s main gyroscope sensor.</p>
   <p>The <a data-link-type="dfn" href="#gyroscope-sensor-type" id="ref-for-gyroscope-sensor-type①">Gyroscope</a> has an associated <a data-link-type="dfn" href="https://w3c.github.io/sensors/#sensor-permission-names" id="ref-for-sensor-permission-names">sensor permission name</a> which is <a class="idl-code" data-link-type="enum-value" href="https://w3c.github.io/permissions/#dom-permissionname-gyroscope" id="ref-for-dom-permissionname-gyroscope">"gyroscope"</a>.</p>
   <p>A <a data-link-type="dfn" href="https://w3c.github.io/sensors/#latest-reading" id="ref-for-latest-reading">latest reading</a> of a <code class="idl"><a data-link-type="idl" href="https://w3c.github.io/sensors/#sensor" id="ref-for-sensor①">Sensor</a></code> of <a data-link-type="dfn" href="#gyroscope-sensor-type" id="ref-for-gyroscope-sensor-type②">Gyroscope</a> <a data-link-type="dfn" href="https://w3c.github.io/sensors/#sensor-type" id="ref-for-sensor-type①">sensor type</a> includes three <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-entry" id="ref-for-map-entry">entries</a> whose <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-key" id="ref-for-map-key">keys</a> are "x", "y", "z" and whose <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-value" id="ref-for-map-value">values</a> contain current <a data-link-type="dfn" href="#angular-velocity" id="ref-for-angular-velocity">angular
velocity</a> about the corresponding axes.</p>
   <p>The <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="angular-velocity">angular velocity</dfn> is the rate at which the device rotates
about a specified axis in a <a data-link-type="dfn" href="https://w3c.github.io/sensors/#local-coordinate-system" id="ref-for-local-coordinate-system">local coordinate system</a> defined by the device.
Its unit is the radian per second (rad/s) <a data-link-type="biblio" href="#biblio-si">[SI]</a>.</p>
   <p>The sign of the current <a data-link-type="dfn" href="#angular-velocity" id="ref-for-angular-velocity①">angular velocity</a> depends on the rotation direction and
it must be according to the right-hand convention in a <a data-link-type="dfn" href="https://w3c.github.io/sensors/#local-coordinate-system" id="ref-for-local-coordinate-system①">local coordinate system</a> defined by the device, such that positive rotation around an axis is clockwise when
viewed along the positive direction of the axis (see figure below).</p>
   <p><img alt="Device’s local coordinate system and rotation." src="images/gyroscope_sensor_coordinate_system.png" srcset="images/gyroscope_sensor_coordinate_system.svg"></p>
   <h3 class="heading settled" data-level="5.1" id="reference-frame"><span class="secno">5.1. </span><span class="content">Reference Frame</span><a class="self-link" href="#reference-frame"></a></h3>
   <p>The <a data-link-type="dfn" href="https://w3c.github.io/sensors/#local-coordinate-system" id="ref-for-local-coordinate-system②">local coordinate system</a> represents the reference frame for the <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope①">Gyroscope</a></code> <a data-link-type="dfn" href="https://w3c.github.io/sensors/#sensor-reading" id="ref-for-sensor-reading②">readings</a>. It can be either
the <a data-link-type="dfn" href="https://w3c.github.io/accelerometer/#device-coordinate-system" id="ref-for-device-coordinate-system">device coordinate system</a> or the <a data-link-type="dfn" href="https://w3c.github.io/accelerometer/#screen-coordinate-system" id="ref-for-screen-coordinate-system">screen coordinate system</a>.</p>
   <h2 class="heading settled" data-level="6" id="api"><span class="secno">6. </span><span class="content">API</span><a class="self-link" href="#api"></a></h2>
   <h3 class="heading settled" data-level="6.1" id="gyroscope-interface"><span class="secno">6.1. </span><span class="content">The Gyroscope Interface</span><a class="self-link" href="#gyroscope-interface"></a></h3>
<pre class="idl highlight def">[<a class="idl-code" data-link-type="extended-attribute" href="https://heycam.github.io/webidl/#SecureContext" id="ref-for-SecureContext"><c- g>SecureContext</c-></a>, <a class="idl-code" data-link-type="extended-attribute" href="https://heycam.github.io/webidl/#Exposed" id="ref-for-Exposed"><c- g>Exposed</c-></a>=<c- n>Window</c->]
<c- b>interface</c-> <dfn class="dfn-paneled idl-code" data-dfn-type="interface" data-export id="gyroscope"><code><c- g>Gyroscope</c-></code></dfn> : <a class="n" data-link-type="idl-name" href="https://w3c.github.io/sensors/#sensor" id="ref-for-sensor②"><c- n>Sensor</c-></a> {
  <dfn class="idl-code" data-dfn-for="Gyroscope" data-dfn-type="constructor" data-export data-lt="Gyroscope(sensorOptions)|constructor(sensorOptions)|Gyroscope()|constructor()" id="dom-gyroscope-gyroscope"><code><c- g>constructor</c-></code><a class="self-link" href="#dom-gyroscope-gyroscope"></a></dfn>(<c- b>optional</c-> <a class="n" data-link-type="idl-name" href="#dictdef-gyroscopesensoroptions" id="ref-for-dictdef-gyroscopesensoroptions"><c- n>GyroscopeSensorOptions</c-></a> <dfn class="idl-code" data-dfn-for="Gyroscope/Gyroscope(sensorOptions), Gyroscope/constructor(sensorOptions), Gyroscope/Gyroscope(), Gyroscope/constructor()" data-dfn-type="argument" data-export id="dom-gyroscope-gyroscope-sensoroptions-sensoroptions"><code><c- g>sensorOptions</c-></code><a class="self-link" href="#dom-gyroscope-gyroscope-sensoroptions-sensoroptions"></a></dfn> = {});
  <c- b>readonly</c-> <c- b>attribute</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double"><c- b>double</c-></a>? <dfn class="dfn-paneled idl-code" data-dfn-for="Gyroscope" data-dfn-type="attribute" data-export data-readonly data-type="double?" id="dom-gyroscope-x"><code><c- g>x</c-></code></dfn>;
  <c- b>readonly</c-> <c- b>attribute</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double①"><c- b>double</c-></a>? <dfn class="dfn-paneled idl-code" data-dfn-for="Gyroscope" data-dfn-type="attribute" data-export data-readonly data-type="double?" id="dom-gyroscope-y"><code><c- g>y</c-></code></dfn>;
  <c- b>readonly</c-> <c- b>attribute</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double②"><c- b>double</c-></a>? <dfn class="dfn-paneled idl-code" data-dfn-for="Gyroscope" data-dfn-type="attribute" data-export data-readonly data-type="double?" id="dom-gyroscope-z"><code><c- g>z</c-></code></dfn>;
};

<c- b>enum</c-> <dfn class="dfn-paneled idl-code" data-dfn-type="enum" data-export id="enumdef-gyroscopelocalcoordinatesystem"><code><c- g>GyroscopeLocalCoordinateSystem</c-></code></dfn> { <dfn class="idl-code" data-dfn-for="GyroscopeLocalCoordinateSystem" data-dfn-type="enum-value" data-export id="dom-gyroscopelocalcoordinatesystem-device"><code><c- s>"device"</c-></code><a class="self-link" href="#dom-gyroscopelocalcoordinatesystem-device"></a></dfn>, <dfn class="idl-code" data-dfn-for="GyroscopeLocalCoordinateSystem" data-dfn-type="enum-value" data-export id="dom-gyroscopelocalcoordinatesystem-screen"><code><c- s>"screen"</c-></code><a class="self-link" href="#dom-gyroscopelocalcoordinatesystem-screen"></a></dfn> };

<c- b>dictionary</c-> <dfn class="dfn-paneled idl-code" data-dfn-type="dictionary" data-export id="dictdef-gyroscopesensoroptions"><code><c- g>GyroscopeSensorOptions</c-></code></dfn> : <a class="n" data-link-type="idl-name" href="https://w3c.github.io/sensors/#dictdef-sensoroptions" id="ref-for-dictdef-sensoroptions"><c- n>SensorOptions</c-></a> {
  <a class="n" data-link-type="idl-name" href="#enumdef-gyroscopelocalcoordinatesystem" id="ref-for-enumdef-gyroscopelocalcoordinatesystem"><c- n>GyroscopeLocalCoordinateSystem</c-></a> <dfn class="dfn-paneled idl-code" data-default="&quot;device&quot;" data-dfn-for="GyroscopeSensorOptions" data-dfn-type="dict-member" data-export data-type="GyroscopeLocalCoordinateSystem " id="dom-gyroscopesensoroptions-referenceframe"><code><c- g>referenceFrame</c-></code></dfn> = "device";
};
</pre>
   <p>To construct a <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope②">Gyroscope</a></code> object the user agent must invoke
the <a data-link-type="dfn" href="#construct-a-gyroscope-object" id="ref-for-construct-a-gyroscope-object">construct a gyroscope object</a> abstract operation.</p>
   <p><a data-link-type="dfn" href="https://w3c.github.io/sensors/#supported-sensor-options" id="ref-for-supported-sensor-options">Supported sensor options</a> for <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope③">Gyroscope</a></code> are
"frequency" and "referenceFrame".</p>
   <h4 class="heading settled" data-level="6.1.1" id="gyroscope-x"><span class="secno">6.1.1. </span><span class="content">Gyroscope.x</span><a class="self-link" href="#gyroscope-x"></a></h4>
   <p>The <code class="idl"><a class="idl-code" data-link-type="attribute" href="#dom-gyroscope-x" id="ref-for-dom-gyroscope-x">x</a></code> attribute of the <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope④">Gyroscope</a></code> interface represents the current <a data-link-type="dfn" href="#angular-velocity" id="ref-for-angular-velocity②">angular velocity</a> around X-axis.
In other words, this attribute returns the result of invoking <a data-link-type="dfn" href="https://w3c.github.io/sensors/#get-value-from-latest-reading" id="ref-for-get-value-from-latest-reading">get value from latest reading</a> with <emu-val>this</emu-val> and "x" as arguments.</p>
   <h4 class="heading settled" data-level="6.1.2" id="gyroscope-y"><span class="secno">6.1.2. </span><span class="content">Gyroscope.y</span><a class="self-link" href="#gyroscope-y"></a></h4>
   <p>The <code class="idl"><a class="idl-code" data-link-type="attribute" href="#dom-gyroscope-y" id="ref-for-dom-gyroscope-y">y</a></code> attribute of the <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope⑤">Gyroscope</a></code> interface represents the current <a data-link-type="dfn" href="#angular-velocity" id="ref-for-angular-velocity③">angular velocity</a> around Y-axis.
In other words, this attribute returns the result of invoking <a data-link-type="dfn" href="https://w3c.github.io/sensors/#get-value-from-latest-reading" id="ref-for-get-value-from-latest-reading①">get value from latest reading</a> with <emu-val>this</emu-val> and "y" as arguments.</p>
   <h4 class="heading settled" data-level="6.1.3" id="gyroscope-z"><span class="secno">6.1.3. </span><span class="content">Gyroscope.z</span><a class="self-link" href="#gyroscope-z"></a></h4>
   <p>The <code class="idl"><a class="idl-code" data-link-type="attribute" href="#dom-gyroscope-z" id="ref-for-dom-gyroscope-z">z</a></code> attribute of the <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope⑥">Gyroscope</a></code> interface represents the current <a data-link-type="dfn" href="#angular-velocity" id="ref-for-angular-velocity④">angular velocity</a> around Z-axis.
In other words, this attribute returns the result of invoking <a data-link-type="dfn" href="https://w3c.github.io/sensors/#get-value-from-latest-reading" id="ref-for-get-value-from-latest-reading②">get value from latest reading</a> with <emu-val>this</emu-val> and "z" as arguments.</p>
   <h2 class="heading settled" data-level="7" id="abstract-operations"><span class="secno">7. </span><span class="content">Abstract Operations</span><a class="self-link" href="#abstract-operations"></a></h2>
   <h3 class="heading settled dfn-paneled" data-dfn-type="dfn" data-export data-level="7.1" data-lt="Construct a Gyroscope object" id="construct-a-gyroscope-object"><span class="secno">7.1. </span><span class="content">Construct a Gyroscope object</span></h3>
   <div class="algorithm" data-algorithm="construct a gyroscope object">
    <dl>
     <dt data-md>input
     <dd data-md>
      <p><var>options</var>, a <code class="idl"><a data-link-type="idl" href="#dictdef-gyroscopesensoroptions" id="ref-for-dictdef-gyroscopesensoroptions①">GyroscopeSensorOptions</a></code> object.</p>
     <dt data-md>output
     <dd data-md>
      <p>A <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope⑦">Gyroscope</a></code> object.</p>
    </dl>
    <ol>
     <li data-md>
      <p>Let <var>allowed</var> be the result of invoking <a data-link-type="dfn" href="https://w3c.github.io/sensors/#check-sensor-policy-controlled-features" id="ref-for-check-sensor-policy-controlled-features">check sensor policy-controlled features</a> with <a data-link-type="dfn" href="#gyroscope-sensor-type" id="ref-for-gyroscope-sensor-type③">Gyroscope</a>.</p>
     <li data-md>
      <p>If <var>allowed</var> is false, then:</p>
      <ol>
       <li data-md>
        <p><a data-link-type="dfn" href="https://heycam.github.io/webidl/#dfn-throw" id="ref-for-dfn-throw">Throw</a> a <code class="idl"><a data-link-type="idl" href="https://heycam.github.io/webidl/#securityerror" id="ref-for-securityerror">SecurityError</a></code> <code class="idl"><a data-link-type="idl" href="https://heycam.github.io/webidl/#idl-DOMException" id="ref-for-idl-DOMException">DOMException</a></code>.</p>
      </ol>
     <li data-md>
      <p>Let <var>gyroscope</var> be the new <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope⑧">Gyroscope</a></code> object.</p>
     <li data-md>
      <p>Invoke <a data-link-type="dfn" href="https://w3c.github.io/sensors/#initialize-a-sensor-object" id="ref-for-initialize-a-sensor-object">initialize a sensor object</a> with <var>gyroscope</var> and <var>options</var>.</p>
     <li data-md>
      <p>If <var>options</var>.<code class="idl"><a class="idl-code" data-link-type="dict-member" href="#dom-gyroscopesensoroptions-referenceframe" id="ref-for-dom-gyroscopesensoroptions-referenceframe">referenceFrame</a></code> is "screen", then:</p>
      <ol>
       <li data-md>
        <p>Define <a data-link-type="dfn" href="https://w3c.github.io/sensors/#local-coordinate-system" id="ref-for-local-coordinate-system③">local coordinate system</a> for <var>gyroscope</var> as the <a data-link-type="dfn" href="https://w3c.github.io/accelerometer/#screen-coordinate-system" id="ref-for-screen-coordinate-system①">screen coordinate system</a>.</p>
      </ol>
     <li data-md>
      <p>Otherwise, define <a data-link-type="dfn" href="https://w3c.github.io/sensors/#local-coordinate-system" id="ref-for-local-coordinate-system④">local coordinate system</a> for <var>gyroscope</var> as the <a data-link-type="dfn" href="https://w3c.github.io/accelerometer/#device-coordinate-system" id="ref-for-device-coordinate-system①">device coordinate system</a>.</p>
     <li data-md>
      <p>Return <var>gyroscope</var>.</p>
    </ol>
   </div>
   <h2 class="heading settled" data-level="8" id="automation"><span class="secno">8. </span><span class="content">Automation</span><a class="self-link" href="#automation"></a></h2>
    This section extends the <a data-link-type="dfn" href="https://w3c.github.io/sensors/#automation" id="ref-for-automation">automation</a> section defined in the Generic Sensor API <a data-link-type="biblio" href="#biblio-generic-sensor">[GENERIC-SENSOR]</a> to provide mocking information about the rate of rotation around the device’s local three primary axes
for the purposes of testing a user agent’s implementation of <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope⑨">Gyroscope</a></code> API. 
   <h3 class="heading settled" data-level="8.1" id="mock-gyroscope-type"><span class="secno">8.1. </span><span class="content">Mock Sensor Type</span><a class="self-link" href="#mock-gyroscope-type"></a></h3>
   <p>The <code class="idl"><a data-link-type="idl" href="#gyroscope" id="ref-for-gyroscope①⓪">Gyroscope</a></code> class has an associated <a data-link-type="dfn" href="https://w3c.github.io/sensors/#mock-sensor-type" id="ref-for-mock-sensor-type">mock sensor type</a> which is <a class="idl-code" data-link-type="enum-value" href="https://w3c.github.io/sensors/#dom-mocksensortype-gyroscope" id="ref-for-dom-mocksensortype-gyroscope">"gyroscope"</a>, its <a data-link-type="dfn" href="https://w3c.github.io/sensors/#mock-sensor-reading-values" id="ref-for-mock-sensor-reading-values">mock sensor reading values</a> dictionary is defined as follows:</p>
<pre class="idl highlight def"><c- b>dictionary</c-> <dfn class="idl-code" data-dfn-type="dictionary" data-export id="dictdef-gyroscopereadingvalues"><code><c- g>GyroscopeReadingValues</c-></code><a class="self-link" href="#dictdef-gyroscopereadingvalues"></a></dfn> {
  <c- b>required</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double③"><c- b>double</c-></a>? <dfn class="idl-code" data-dfn-for="GyroscopeReadingValues" data-dfn-type="dict-member" data-export data-type="double? " id="dom-gyroscopereadingvalues-x"><code><c- g>x</c-></code><a class="self-link" href="#dom-gyroscopereadingvalues-x"></a></dfn>;
  <c- b>required</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double④"><c- b>double</c-></a>? <dfn class="idl-code" data-dfn-for="GyroscopeReadingValues" data-dfn-type="dict-member" data-export data-type="double? " id="dom-gyroscopereadingvalues-y"><code><c- g>y</c-></code><a class="self-link" href="#dom-gyroscopereadingvalues-y"></a></dfn>;
  <c- b>required</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double⑤"><c- b>double</c-></a>? <dfn class="idl-code" data-dfn-for="GyroscopeReadingValues" data-dfn-type="dict-member" data-export data-type="double? " id="dom-gyroscopereadingvalues-z"><code><c- g>z</c-></code><a class="self-link" href="#dom-gyroscopereadingvalues-z"></a></dfn>;
};
</pre>
   <h2 class="heading settled" data-level="9" id="acknowledgements"><span class="secno">9. </span><span class="content">Acknowledgements</span><a class="self-link" href="#acknowledgements"></a></h2>
   <p>Tobie Langel for the work on Generic Sensor API.</p>
   <h2 class="heading settled" data-level="10" id="conformance"><span class="secno">10. </span><span class="content">Conformance</span><a class="self-link" href="#conformance"></a></h2>
   <p>Conformance requirements are expressed with a combination of
descriptive assertions and RFC 2119 terminology. The key words "MUST",
"MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT",
"RECOMMENDED", "MAY", and "OPTIONAL" in the normative parts of this
document are to be interpreted as described in RFC 2119.
However, for readability, these words do not appear in all uppercase
letters in this specification.</p>
   <p>All of the text of this specification is normative except sections
explicitly marked as non-normative, examples, and notes. <a data-link-type="biblio" href="#biblio-rfc2119">[RFC2119]</a></p>
   <p>A <dfn data-dfn-type="dfn" data-noexport id="conformant-user-agent">conformant user agent<a class="self-link" href="#conformant-user-agent"></a></dfn> must implement all the requirements
listed in this specification that are applicable to user agents.</p>
   <p>The IDL fragments in this specification must be interpreted as required for
conforming IDL fragments, as described in the Web IDL specification. <a data-link-type="biblio" href="#biblio-webidl">[WEBIDL]</a></p>
  </main>
<script src="https://www.w3.org/scripts/TR/2016/fixup.js"></script>
  <h2 class="no-num no-ref heading settled" id="index"><span class="content">Index</span><a class="self-link" href="#index"></a></h2>
  <h3 class="no-num no-ref heading settled" id="index-defined-here"><span class="content">Terms defined by this specification</span><a class="self-link" href="#index-defined-here"></a></h3>
  <ul class="index">
   <li><a href="#angular-velocity">angular velocity</a><span>, in §5</span>
   <li><a href="#conformant-user-agent">conformant user agent</a><span>, in §10</span>
   <li><a href="#construct-a-gyroscope-object">Construct a Gyroscope object</a><span>, in §7</span>
   <li><a href="#dom-gyroscope-gyroscope">constructor()</a><span>, in §6.1</span>
   <li><a href="#dom-gyroscope-gyroscope">constructor(sensorOptions)</a><span>, in §6.1</span>
   <li><a href="#dom-gyroscopelocalcoordinatesystem-device">"device"</a><span>, in §6.1</span>
   <li><a href="#dom-gyroscope-gyroscope">Gyroscope()</a><span>, in §6.1</span>
   <li>
    Gyroscope
    <ul>
     <li><a href="#gyroscope">(interface)</a><span>, in §6.1</span>
     <li><a href="#gyroscope-sensor-type">definition of</a><span>, in §5</span>
    </ul>
   <li><a href="#enumdef-gyroscopelocalcoordinatesystem">GyroscopeLocalCoordinateSystem</a><span>, in §6.1</span>
   <li><a href="#dictdef-gyroscopereadingvalues">GyroscopeReadingValues</a><span>, in §8.1</span>
   <li><a href="#dom-gyroscope-gyroscope">Gyroscope(sensorOptions)</a><span>, in §6.1</span>
   <li><a href="#dictdef-gyroscopesensoroptions">GyroscopeSensorOptions</a><span>, in §6.1</span>
   <li><a href="#dom-gyroscopesensoroptions-referenceframe">referenceFrame</a><span>, in §6.1</span>
   <li><a href="#dom-gyroscopelocalcoordinatesystem-screen">"screen"</a><span>, in §6.1</span>
   <li>
    x
    <ul>
     <li><a href="#dom-gyroscope-x">attribute for Gyroscope</a><span>, in §6.1</span>
     <li><a href="#dom-gyroscopereadingvalues-x">dict-member for GyroscopeReadingValues</a><span>, in §8.1</span>
    </ul>
   <li>
    y
    <ul>
     <li><a href="#dom-gyroscope-y">attribute for Gyroscope</a><span>, in §6.1</span>
     <li><a href="#dom-gyroscopereadingvalues-y">dict-member for GyroscopeReadingValues</a><span>, in §8.1</span>
    </ul>
   <li>
    z
    <ul>
     <li><a href="#dom-gyroscope-z">attribute for Gyroscope</a><span>, in §6.1</span>
     <li><a href="#dom-gyroscopereadingvalues-z">dict-member for GyroscopeReadingValues</a><span>, in §8.1</span>
    </ul>
  </ul>
  <aside class="dfn-panel" data-for="term-for-device-coordinate-system">
   <a href="https://w3c.github.io/accelerometer/#device-coordinate-system">https://w3c.github.io/accelerometer/#device-coordinate-system</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-device-coordinate-system">5.1. Reference Frame</a>
    <li><a href="#ref-for-device-coordinate-system①">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-screen-coordinate-system">
   <a href="https://w3c.github.io/accelerometer/#screen-coordinate-system">https://w3c.github.io/accelerometer/#screen-coordinate-system</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-screen-coordinate-system">5.1. Reference Frame</a>
    <li><a href="#ref-for-screen-coordinate-system①">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-dom-mocksensortype-gyroscope">
   <a href="https://w3c.github.io/sensors/#dom-mocksensortype-gyroscope">https://w3c.github.io/sensors/#dom-mocksensortype-gyroscope</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dom-mocksensortype-gyroscope">8.1. Mock Sensor Type</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-sensor">
   <a href="https://w3c.github.io/sensors/#sensor">https://w3c.github.io/sensors/#sensor</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-sensor">5. Model</a> <a href="#ref-for-sensor①">(2)</a>
    <li><a href="#ref-for-sensor②">6.1. The Gyroscope Interface</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-dictdef-sensoroptions">
   <a href="https://w3c.github.io/sensors/#dictdef-sensoroptions">https://w3c.github.io/sensors/#dictdef-sensoroptions</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dictdef-sensoroptions">6.1. The Gyroscope Interface</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-automation">
   <a href="https://w3c.github.io/sensors/#automation">https://w3c.github.io/sensors/#automation</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-automation">8. Automation</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-check-sensor-policy-controlled-features">
   <a href="https://w3c.github.io/sensors/#check-sensor-policy-controlled-features">https://w3c.github.io/sensors/#check-sensor-policy-controlled-features</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-check-sensor-policy-controlled-features">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-default-sensor">
   <a href="https://w3c.github.io/sensors/#default-sensor">https://w3c.github.io/sensors/#default-sensor</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-default-sensor">5. Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-eavesdropping">
   <a href="https://w3c.github.io/sensors/#eavesdropping">https://w3c.github.io/sensors/#eavesdropping</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-eavesdropping">4. Security and Privacy Considerations</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-device-fingerprinting">
   <a href="https://w3c.github.io/sensors/#device-fingerprinting">https://w3c.github.io/sensors/#device-fingerprinting</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-device-fingerprinting">4. Security and Privacy Considerations</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-mitigation-strategies">
   <a href="https://w3c.github.io/sensors/#mitigation-strategies">https://w3c.github.io/sensors/#mitigation-strategies</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-mitigation-strategies">4. Security and Privacy Considerations</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-get-value-from-latest-reading">
   <a href="https://w3c.github.io/sensors/#get-value-from-latest-reading">https://w3c.github.io/sensors/#get-value-from-latest-reading</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-get-value-from-latest-reading">6.1.1. Gyroscope.x</a>
    <li><a href="#ref-for-get-value-from-latest-reading①">6.1.2. Gyroscope.y</a>
    <li><a href="#ref-for-get-value-from-latest-reading②">6.1.3. Gyroscope.z</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-initialize-a-sensor-object">
   <a href="https://w3c.github.io/sensors/#initialize-a-sensor-object">https://w3c.github.io/sensors/#initialize-a-sensor-object</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-initialize-a-sensor-object">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-keystroke-monitoring">
   <a href="https://w3c.github.io/sensors/#keystroke-monitoring">https://w3c.github.io/sensors/#keystroke-monitoring</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-keystroke-monitoring">4. Security and Privacy Considerations</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-latest-reading">
   <a href="https://w3c.github.io/sensors/#latest-reading">https://w3c.github.io/sensors/#latest-reading</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-latest-reading">5. Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-local-coordinate-system">
   <a href="https://w3c.github.io/sensors/#local-coordinate-system">https://w3c.github.io/sensors/#local-coordinate-system</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-local-coordinate-system">5. Model</a> <a href="#ref-for-local-coordinate-system①">(2)</a>
    <li><a href="#ref-for-local-coordinate-system②">5.1. Reference Frame</a>
    <li><a href="#ref-for-local-coordinate-system③">7.1. Construct a Gyroscope object</a> <a href="#ref-for-local-coordinate-system④">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-location-tracking">
   <a href="https://w3c.github.io/sensors/#location-tracking">https://w3c.github.io/sensors/#location-tracking</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-location-tracking">4. Security and Privacy Considerations</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-mock-sensor-reading-values">
   <a href="https://w3c.github.io/sensors/#mock-sensor-reading-values">https://w3c.github.io/sensors/#mock-sensor-reading-values</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-mock-sensor-reading-values">8.1. Mock Sensor Type</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-mock-sensor-type">
   <a href="https://w3c.github.io/sensors/#mock-sensor-type">https://w3c.github.io/sensors/#mock-sensor-type</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-mock-sensor-type">8.1. Mock Sensor Type</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-sensor-permission-names">
   <a href="https://w3c.github.io/sensors/#sensor-permission-names">https://w3c.github.io/sensors/#sensor-permission-names</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-sensor-permission-names">5. Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-sensor-reading">
   <a href="https://w3c.github.io/sensors/#sensor-reading">https://w3c.github.io/sensors/#sensor-reading</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-sensor-reading">4. Security and Privacy Considerations</a> <a href="#ref-for-sensor-reading①">(2)</a>
    <li><a href="#ref-for-sensor-reading②">5.1. Reference Frame</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-sensor-type">
   <a href="https://w3c.github.io/sensors/#sensor-type">https://w3c.github.io/sensors/#sensor-type</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-sensor-type">5. Model</a> <a href="#ref-for-sensor-type①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-supported-sensor-options">
   <a href="https://w3c.github.io/sensors/#supported-sensor-options">https://w3c.github.io/sensors/#supported-sensor-options</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-supported-sensor-options">6.1. The Gyroscope Interface</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-user-identifying">
   <a href="https://w3c.github.io/sensors/#user-identifying">https://w3c.github.io/sensors/#user-identifying</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-user-identifying">4. Security and Privacy Considerations</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-map-entry">
   <a href="https://infra.spec.whatwg.org/#map-entry">https://infra.spec.whatwg.org/#map-entry</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-map-entry">5. Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-map-key">
   <a href="https://infra.spec.whatwg.org/#map-key">https://infra.spec.whatwg.org/#map-key</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-map-key">5. Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-map-value">
   <a href="https://infra.spec.whatwg.org/#map-value">https://infra.spec.whatwg.org/#map-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-map-value">5. Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-dom-permissionname-gyroscope">
   <a href="https://w3c.github.io/permissions/#dom-permissionname-gyroscope">https://w3c.github.io/permissions/#dom-permissionname-gyroscope</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dom-permissionname-gyroscope">5. Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-idl-DOMException">
   <a href="https://heycam.github.io/webidl/#idl-DOMException">https://heycam.github.io/webidl/#idl-DOMException</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-idl-DOMException">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-Exposed">
   <a href="https://heycam.github.io/webidl/#Exposed">https://heycam.github.io/webidl/#Exposed</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-Exposed">6.1. The Gyroscope Interface</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-SecureContext">
   <a href="https://heycam.github.io/webidl/#SecureContext">https://heycam.github.io/webidl/#SecureContext</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-SecureContext">6.1. The Gyroscope Interface</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-securityerror">
   <a href="https://heycam.github.io/webidl/#securityerror">https://heycam.github.io/webidl/#securityerror</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-securityerror">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-idl-double">
   <a href="https://heycam.github.io/webidl/#idl-double">https://heycam.github.io/webidl/#idl-double</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-idl-double">6.1. The Gyroscope Interface</a> <a href="#ref-for-idl-double①">(2)</a> <a href="#ref-for-idl-double②">(3)</a>
    <li><a href="#ref-for-idl-double③">8.1. Mock Sensor Type</a> <a href="#ref-for-idl-double④">(2)</a> <a href="#ref-for-idl-double⑤">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-dfn-throw">
   <a href="https://heycam.github.io/webidl/#dfn-throw">https://heycam.github.io/webidl/#dfn-throw</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dfn-throw">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <h3 class="no-num no-ref heading settled" id="index-defined-elsewhere"><span class="content">Terms defined by reference</span><a class="self-link" href="#index-defined-elsewhere"></a></h3>
  <ul class="index">
   <li>
    <a data-link-type="biblio">[accelerometer]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-device-coordinate-system" style="color:initial">device coordinate system</span>
     <li><span class="dfn-paneled" id="term-for-screen-coordinate-system" style="color:initial">screen coordinate system</span>
    </ul>
   <li>
    <a data-link-type="biblio">[GENERIC-SENSOR]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-dom-mocksensortype-gyroscope" style="color:initial">"gyroscope"</span>
     <li><span class="dfn-paneled" id="term-for-sensor" style="color:initial">Sensor</span>
     <li><span class="dfn-paneled" id="term-for-dictdef-sensoroptions" style="color:initial">SensorOptions</span>
     <li><span class="dfn-paneled" id="term-for-automation" style="color:initial">automation</span>
     <li><span class="dfn-paneled" id="term-for-check-sensor-policy-controlled-features" style="color:initial">check sensor policy-controlled features</span>
     <li><span class="dfn-paneled" id="term-for-default-sensor" style="color:initial">default sensor</span>
     <li><span class="dfn-paneled" id="term-for-eavesdropping" style="color:initial">eavesdropping</span>
     <li><span class="dfn-paneled" id="term-for-device-fingerprinting" style="color:initial">fingerprinting</span>
     <li><span class="dfn-paneled" id="term-for-mitigation-strategies" style="color:initial">generic mitigations</span>
     <li><span class="dfn-paneled" id="term-for-get-value-from-latest-reading" style="color:initial">get value from latest reading</span>
     <li><span class="dfn-paneled" id="term-for-initialize-a-sensor-object" style="color:initial">initialize a sensor object</span>
     <li><span class="dfn-paneled" id="term-for-keystroke-monitoring" style="color:initial">keylogging</span>
     <li><span class="dfn-paneled" id="term-for-latest-reading" style="color:initial">latest reading</span>
     <li><span class="dfn-paneled" id="term-for-local-coordinate-system" style="color:initial">local coordinate system</span>
     <li><span class="dfn-paneled" id="term-for-location-tracking" style="color:initial">location tracking</span>
     <li><span class="dfn-paneled" id="term-for-mock-sensor-reading-values" style="color:initial">mock sensor reading values</span>
     <li><span class="dfn-paneled" id="term-for-mock-sensor-type" style="color:initial">mock sensor type</span>
     <li><span class="dfn-paneled" id="term-for-sensor-permission-names" style="color:initial">sensor permission name</span>
     <li><span class="dfn-paneled" id="term-for-sensor-reading" style="color:initial">sensor reading</span>
     <li><span class="dfn-paneled" id="term-for-sensor-type" style="color:initial">sensor type</span>
     <li><span class="dfn-paneled" id="term-for-supported-sensor-options" style="color:initial">supported sensor options</span>
     <li><span class="dfn-paneled" id="term-for-user-identifying" style="color:initial">user identifying</span>
    </ul>
   <li>
    <a data-link-type="biblio">[INFRA]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-map-entry" style="color:initial">entry</span>
     <li><span class="dfn-paneled" id="term-for-map-key" style="color:initial">key</span>
     <li><span class="dfn-paneled" id="term-for-map-value" style="color:initial">value</span>
    </ul>
   <li>
    <a data-link-type="biblio">[permissions]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-dom-permissionname-gyroscope" style="color:initial">"gyroscope"</span>
    </ul>
   <li>
    <a data-link-type="biblio">[WEBIDL]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-idl-DOMException" style="color:initial">DOMException</span>
     <li><span class="dfn-paneled" id="term-for-Exposed" style="color:initial">Exposed</span>
     <li><span class="dfn-paneled" id="term-for-SecureContext" style="color:initial">SecureContext</span>
     <li><span class="dfn-paneled" id="term-for-securityerror" style="color:initial">SecurityError</span>
     <li><span class="dfn-paneled" id="term-for-idl-double" style="color:initial">double</span>
     <li><span class="dfn-paneled" id="term-for-dfn-throw" style="color:initial">throw</span>
    </ul>
  </ul>
  <h2 class="no-num no-ref heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
  <h3 class="no-num no-ref heading settled" id="normative"><span class="content">Normative References</span><a class="self-link" href="#normative"></a></h3>
  <dl>
   <dt id="biblio-accelerometer">[ACCELEROMETER]
   <dd>Anssi Kostiainen. <a href="https://w3c.github.io/accelerometer/">Accelerometer</a>. URL: <a href="https://w3c.github.io/accelerometer/">https://w3c.github.io/accelerometer/</a>
   <dt id="biblio-generic-sensor">[GENERIC-SENSOR]
   <dd>Mikhail Pozdnyakov; Alexander Shalamov; Tobie Langel. <a href="https://w3c.github.io/sensors/">Generic Sensor API</a>. URL: <a href="https://w3c.github.io/sensors/">https://w3c.github.io/sensors/</a>
   <dt id="biblio-infra">[INFRA]
   <dd>Anne van Kesteren; Domenic Denicola. <a href="https://infra.spec.whatwg.org/">Infra Standard</a>. Living Standard. URL: <a href="https://infra.spec.whatwg.org/">https://infra.spec.whatwg.org/</a>
   <dt id="biblio-permissions">[PERMISSIONS]
   <dd>Mounir Lamouri; Marcos Caceres; Jeffrey Yasskin. <a href="https://w3c.github.io/permissions/">Permissions</a>. URL: <a href="https://w3c.github.io/permissions/">https://w3c.github.io/permissions/</a>
   <dt id="biblio-rfc2119">[RFC2119]
   <dd>S. Bradner. <a href="https://tools.ietf.org/html/rfc2119">Key words for use in RFCs to Indicate Requirement Levels</a>. March 1997. Best Current Practice. URL: <a href="https://tools.ietf.org/html/rfc2119">https://tools.ietf.org/html/rfc2119</a>
   <dt id="biblio-webidl">[WEBIDL]
   <dd>Boris Zbarsky. <a href="https://heycam.github.io/webidl/">Web IDL</a>. URL: <a href="https://heycam.github.io/webidl/">https://heycam.github.io/webidl/</a>
  </dl>
  <h3 class="no-num no-ref heading settled" id="informative"><span class="content">Informative References</span><a class="self-link" href="#informative"></a></h3>
  <dl>
   <dt id="biblio-keystrokedefense">[KEYSTROKEDEFENSE]
   <dd>Song, Yihang, et al. <a href="https://arxiv.org/abs/1410.7746">Two novel defenses against motion-based keystroke inference attacks</a>. 2014. Informational. URL: <a href="https://arxiv.org/abs/1410.7746">https://arxiv.org/abs/1410.7746</a>
   <dt id="biblio-si">[SI]
   <dd><a href="http://www.bipm.org/en/publications/si-brochure/">SI Brochure: The International System of Units (SI), 8th edition</a>. 2014. URL: <a href="http://www.bipm.org/en/publications/si-brochure/">http://www.bipm.org/en/publications/si-brochure/</a>
   <dt id="biblio-touchsignatures">[TOUCHSIGNATURES]
   <dd>Mehrnezhad, Maryam, et al. <a href="https://arxiv.org/abs/1602.04115">Touchsignatures: identification of user touch actions and pins based on mobile sensor data via javascript</a>. 2016. Informational. URL: <a href="https://arxiv.org/abs/1602.04115">https://arxiv.org/abs/1602.04115</a>
  </dl>
  <h2 class="no-num no-ref heading settled" id="idl-index"><span class="content">IDL Index</span><a class="self-link" href="#idl-index"></a></h2>
<pre class="idl highlight def">[<a class="idl-code" data-link-type="extended-attribute" href="https://heycam.github.io/webidl/#SecureContext" id="ref-for-SecureContext①"><c- g>SecureContext</c-></a>, <a class="idl-code" data-link-type="extended-attribute" href="https://heycam.github.io/webidl/#Exposed" id="ref-for-Exposed①"><c- g>Exposed</c-></a>=<c- n>Window</c->]
<c- b>interface</c-> <a href="#gyroscope"><code><c- g>Gyroscope</c-></code></a> : <a class="n" data-link-type="idl-name" href="https://w3c.github.io/sensors/#sensor" id="ref-for-sensor②①"><c- n>Sensor</c-></a> {
  <a href="#dom-gyroscope-gyroscope"><code><c- g>constructor</c-></code></a>(<c- b>optional</c-> <a class="n" data-link-type="idl-name" href="#dictdef-gyroscopesensoroptions" id="ref-for-dictdef-gyroscopesensoroptions②"><c- n>GyroscopeSensorOptions</c-></a> <a href="#dom-gyroscope-gyroscope-sensoroptions-sensoroptions"><code><c- g>sensorOptions</c-></code></a> = {});
  <c- b>readonly</c-> <c- b>attribute</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double⑥"><c- b>double</c-></a>? <a data-readonly data-type="double?" href="#dom-gyroscope-x"><code><c- g>x</c-></code></a>;
  <c- b>readonly</c-> <c- b>attribute</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double①①"><c- b>double</c-></a>? <a data-readonly data-type="double?" href="#dom-gyroscope-y"><code><c- g>y</c-></code></a>;
  <c- b>readonly</c-> <c- b>attribute</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double②①"><c- b>double</c-></a>? <a data-readonly data-type="double?" href="#dom-gyroscope-z"><code><c- g>z</c-></code></a>;
};

<c- b>enum</c-> <a href="#enumdef-gyroscopelocalcoordinatesystem"><code><c- g>GyroscopeLocalCoordinateSystem</c-></code></a> { <a href="#dom-gyroscopelocalcoordinatesystem-device"><code><c- s>"device"</c-></code></a>, <a href="#dom-gyroscopelocalcoordinatesystem-screen"><code><c- s>"screen"</c-></code></a> };

<c- b>dictionary</c-> <a href="#dictdef-gyroscopesensoroptions"><code><c- g>GyroscopeSensorOptions</c-></code></a> : <a class="n" data-link-type="idl-name" href="https://w3c.github.io/sensors/#dictdef-sensoroptions" id="ref-for-dictdef-sensoroptions①"><c- n>SensorOptions</c-></a> {
  <a class="n" data-link-type="idl-name" href="#enumdef-gyroscopelocalcoordinatesystem" id="ref-for-enumdef-gyroscopelocalcoordinatesystem①"><c- n>GyroscopeLocalCoordinateSystem</c-></a> <a data-default="&quot;device&quot;" data-type="GyroscopeLocalCoordinateSystem " href="#dom-gyroscopesensoroptions-referenceframe"><code><c- g>referenceFrame</c-></code></a> = "device";
};

<c- b>dictionary</c-> <a href="#dictdef-gyroscopereadingvalues"><code><c- g>GyroscopeReadingValues</c-></code></a> {
  <c- b>required</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double③①"><c- b>double</c-></a>? <a data-type="double? " href="#dom-gyroscopereadingvalues-x"><code><c- g>x</c-></code></a>;
  <c- b>required</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double④①"><c- b>double</c-></a>? <a data-type="double? " href="#dom-gyroscopereadingvalues-y"><code><c- g>y</c-></code></a>;
  <c- b>required</c-> <a class="idl-code" data-link-type="interface" href="https://heycam.github.io/webidl/#idl-double" id="ref-for-idl-double⑤①"><c- b>double</c-></a>? <a data-type="double? " href="#dom-gyroscopereadingvalues-z"><code><c- g>z</c-></code></a>;
};

</pre>
  <aside class="dfn-panel" data-for="gyroscope-sensor-type">
   <b><a href="#gyroscope-sensor-type">#gyroscope-sensor-type</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-gyroscope-sensor-type">5. Model</a> <a href="#ref-for-gyroscope-sensor-type①">(2)</a> <a href="#ref-for-gyroscope-sensor-type②">(3)</a>
    <li><a href="#ref-for-gyroscope-sensor-type③">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="angular-velocity">
   <b><a href="#angular-velocity">#angular-velocity</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-angular-velocity">5. Model</a> <a href="#ref-for-angular-velocity①">(2)</a>
    <li><a href="#ref-for-angular-velocity②">6.1.1. Gyroscope.x</a>
    <li><a href="#ref-for-angular-velocity③">6.1.2. Gyroscope.y</a>
    <li><a href="#ref-for-angular-velocity④">6.1.3. Gyroscope.z</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="gyroscope">
   <b><a href="#gyroscope">#gyroscope</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-gyroscope">5. Model</a>
    <li><a href="#ref-for-gyroscope①">5.1. Reference Frame</a>
    <li><a href="#ref-for-gyroscope②">6.1. The Gyroscope Interface</a> <a href="#ref-for-gyroscope③">(2)</a>
    <li><a href="#ref-for-gyroscope④">6.1.1. Gyroscope.x</a>
    <li><a href="#ref-for-gyroscope⑤">6.1.2. Gyroscope.y</a>
    <li><a href="#ref-for-gyroscope⑥">6.1.3. Gyroscope.z</a>
    <li><a href="#ref-for-gyroscope⑦">7.1. Construct a Gyroscope object</a> <a href="#ref-for-gyroscope⑧">(2)</a>
    <li><a href="#ref-for-gyroscope⑨">8. Automation</a>
    <li><a href="#ref-for-gyroscope①⓪">8.1. Mock Sensor Type</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="dom-gyroscope-x">
   <b><a href="#dom-gyroscope-x">#dom-gyroscope-x</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dom-gyroscope-x">6.1.1. Gyroscope.x</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="dom-gyroscope-y">
   <b><a href="#dom-gyroscope-y">#dom-gyroscope-y</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dom-gyroscope-y">6.1.2. Gyroscope.y</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="dom-gyroscope-z">
   <b><a href="#dom-gyroscope-z">#dom-gyroscope-z</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dom-gyroscope-z">6.1.3. Gyroscope.z</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="enumdef-gyroscopelocalcoordinatesystem">
   <b><a href="#enumdef-gyroscopelocalcoordinatesystem">#enumdef-gyroscopelocalcoordinatesystem</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-enumdef-gyroscopelocalcoordinatesystem">6.1. The Gyroscope Interface</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="dictdef-gyroscopesensoroptions">
   <b><a href="#dictdef-gyroscopesensoroptions">#dictdef-gyroscopesensoroptions</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dictdef-gyroscopesensoroptions">6.1. The Gyroscope Interface</a>
    <li><a href="#ref-for-dictdef-gyroscopesensoroptions①">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="dom-gyroscopesensoroptions-referenceframe">
   <b><a href="#dom-gyroscopesensoroptions-referenceframe">#dom-gyroscopesensoroptions-referenceframe</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dom-gyroscopesensoroptions-referenceframe">7.1. Construct a Gyroscope object</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="construct-a-gyroscope-object">
   <b><a href="#construct-a-gyroscope-object">#construct-a-gyroscope-object</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-construct-a-gyroscope-object">6.1. The Gyroscope Interface</a>
   </ul>
  </aside>
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